The present invention relates to an arrangement for loading and unloading workpieces of a machine tool, such as an automatic lathe.
A loading and unloading arrangement for a machine tool is described in Volume 8, page 485 of the journal "Fertigungstechnik und Betrieb". In this known arrangement swivel arms carrying workpiece conveying elements are arranged in the work space of the machine tool, opposite to the work spindle and diametrically opposite one another with respect to a work-holding fixture. The workpieces are conveyed to and from a holding fixture along arcuate paths which touch each other tangentially in front of the holding fixture. In this arrangement swivel arms are arranged both on the operating side and on the opposite side of the machine space, a stationary workpiece feeding device being associated with one swivel arm and a stationary workpiece unloading device with the other.
This known loading and unloading arrangement can be used with machine tools such as drilling and milling machines particularly machines with a vertically supported work spindle. However, this arrangement is not suitable for use with automatic lathes, and particularly automatic turret lathes, because of its space requirements and also because it requires feeding and unloading devices which both precede and follow the swivel arms.
Arrangements intended for loading and unloading machine tools equipped with a horizontally-supported work spindle, particularly automatic lathes, are also known. However, for various reasons, these known arrangements are not entirely satisfactory for use with modern machine tools, particularly numerically-controlled machine tools, which offer great flexibility.
Briefly, this is due to the manner in which they handle the workpieces and because these known arrangements have a large space requirement and must be placed adjacent to the machine tool. Accordingly, these known arrangements impede access to the work space of the machine tool so that tool changing is made more difficult and is often necessary, to operate these arrangements, to open and close the machine cover which retains the chips and coolants.
It is an object of the invention to provide a loading and unloading arrangement which forms a functional unit without stationary accessories and which can be accommodated in the work space of a machine tool, particularly of numerically-controlled machine tools and of automatic lathes.